I'm totally jealous!!
That's a great accomplishment nowadays. My parents did the same. Bought their house in 1961 for less than $10K and sold it in 1987 for nearly $300,000! The area it was in became one of the more "desired" areas to live. When they bought it the area was pretty much undeveloped. It changed!!
All that $$ took care of my Dad the last several years of his life. Don't know what we'd have done had it not been for that house.
Burn that mortgage!! Or better yet, frame it!